The flapping of a single butterfly's wing today produces a tiny change in the state of the atmosphere. Over a period of time, what the atmosphere actually does diverges from what it would have done. So, in a month's time, a tornado that would have devastated the Indonesian coast doesn't happen. Or maybe one that wasn't going to happen, does. (Ian Stewart, Does God Play Dice? The Mathematics of Chaos, pg. 141)
Flutter is based on the Koch curve and a loose implentation of integral harmonic serialism, further developed through improvisation. It is a semi-abstract piece, based on the metaphor of a fledgling learning to fly.